TM 10-3930-643-34 HYDRAULIC  SYSTEM  TROUBLESHOOTING  AND  MAINTENANCE.  (cont) 12-17. Oscillation Cylinder (S/N 2000 and below). (Sheet 6 of 8) ASSEMBLY 23. Using a 5/16"   socket and socket wrench  handle, install  two  fittings (28) on two pins (10). 24. Coat retainer (13), rod (21) and inside of cylinder shell (12) with clean  hydraulic  fluid. 25. Install retainer (13) on rod (21). NOTE Lubricate  all  preformed  packings, wipers ,   seals. sliding parts and housing  before  installing. 26. Install new retainer bearing (20) on rod (21). 27. Install  new  preformed  packing  (19), two rings (18), new bearing (16) and new seal (17) on piston (15). Lip on seal (17) is to face inside cylinder. 28. Install items 19 thru 15 as an assembly on rod (21). 29. Using  a  adjustable  wrench,  install nut (14) on rod (21). 30. Install items 27 thru 14 as an assembly  in  cylinder  shell  (12). 31. Using  a  spanner  wrench,  tighten retainer  (13)  on  cylinder  assembly (11). Go to sheet 7 12-157